Conventionally, a wiper apparatus is mounted on a vehicle such as automotive vehicle to wipe out rainwater, dust, and the like on a windshield. The wiper apparatus includes a wiper member provided on the windshield and a wiper motor for driving the wiper member for rotation. The wiper motor is driven for rotation with an ON operation of a wiper switch provided in the interior of the vehicle by an operator. Therefore, the wiper member is configured to make a swinging motion on the windshield to wipe out extraneous material.
One example of the wiper motor as described above is disclosed in Japanese Patent Application Laid-Open Publication No. 2010-093977 (FIG. 3). A wiper motor (decelerating-mechanism-equipped wiper motor) described in Japanese Patent Application Laid-Open Publication No. 2010-093977 (FIG. 3) includes a motor part and a decelerating part. The motor part includes a yoke housing made of metal, and a stator having a winding is fixed inside the yoke housing. Furthermore, a rotor is rotatably disposed inside the stator. That is, the motor part of the wiper motor described in Japanese Patent Application Laid-Open Publication No. 2010-093977 (FIG. 3) serves as a brushless motor.
On the other hand, the decelerating part includes a gear housing made of aluminium, a worm portion provided on a rotating shaft of the rotor, and a worm wheel engaged with the worm portion are accommodated in the gear housing. The worm portion and the worm wheel collectively form a decelerating mechanism, the decelerating mechanism is configured to decelerate the rotation of the rotating shaft to increase torque, and the torque-increased rotation is outputted from an output shaft fixed to the worm wheel to the outside.